TREE FROGS. CjECILIAD^E. SALAMANDRID^E. 575 



Frogs, which are common in most temperate and tropical 



regions, although none occur 

 in Britain, are very beautiful 

 and active little animals, 

 dwelling amidst the foliage 

 of the woods, and changing 

 their hues in accordance with 

 the colour of the surrounding 

 objects. There is distinct 

 evidence, derived from im- 

 pressions of footsteps, and 

 from remains of teeth and 



FIG 243. HYLA OR TREE-FROG. , ., ,. , . 



bones, that a gigantic animal 



of the Frog tribe, measuring at least three or four feet in length, 

 inhabited Britain, at the time when the New Red Sandstone 

 was in process of formation ; this has received the name of Laly- 

 rinthodon, from peculiarities in the structure of the teeth. 



513. The Tortoises seem to be represented in this group, by 

 a species of Frog that inhabits Brazil ; in which a sort of 

 carapace and plastron are formed by the thickening of the skin 

 above and below. The Serpents are represented by the very 

 curious family of C^ECILIADJE, which are intermediate in their 

 characters between the two groups, having the form of Serpents, 

 but the naked skin and imperfectly-developed ribs of the Frogs. 

 That their real position is in this order, has been recently proved 

 by the discovery, that they undergo a metamorphosis like the 

 Batrachia in general. The Lizards, too, find their represent- 

 atives in the family SALAMANDRIDJE, or Salamanders; of which 

 we have examples in this country, the Water and Land-Newts, 

 or Efts, bearing much ^yvV^^z. 



the same relation to 

 each other, as do the 

 Frogs and Toads. 

 These are extremely 

 harmless animals, not FIG. 244.-WATER-NBWT. 



at all deserving the aversion with which they are commonly 

 regarded. The Menopoma of the Ohio and Alleghany rivers 



